How many sight words

The main difference between digital radiography (radiovisiography) and traditional radiography is that in this case, instead of a film, the image receiver is a sensor that perceives radiation and transmits information to a computer. The equipment required for radiovisiography sequentially consists of a radiation source, a device for reading information, a device for digitizing information, and a device for reproducing and processing images.

Modern low-dose generators with a minimum timer value are used as a radiation source, designed to work as part of a visualographic complex. The visiograph itself consists of a sensor, which is a sensor based on a CCD or CIMOS matrix, an analog-to-digital converter, and a computer program designed to optimize and store images.

Original digital images may look slightly different from conventional film images at first glance, so they need to be processed using the software options. The highest quality image is the image that is closest to analog in visual perception, therefore, even despite the highest technical characteristics of the visiograph, the quality of the final image largely depends on the capabilities of the program and the specialist’s ability to work with it.

Popular imaging techniques

To date, the most common and popular method of radiation examination in outpatient practice is intraoral radiography of teeth, or an intraoral photograph of a tooth. Sometimes intraoral pictures of teeth are called sighting, which is wrong. A shot is called an image taken outside the standard stacking, and standardized studies are named according to the positioning method.

At a therapeutic appointment during endodontic treatment, at least three intraoral images of each examined tooth must be taken:

• a diagnostic image is necessary for assessing the condition of periodontal tissues at the time of examination, making a diagnosis, determining the number and shape of roots, guiding channels, and choosing treatment tactics.
• measuring image - a photograph of a tooth at the stage of treatment with endodontic instruments inserted into the canals with a fixed stopper length of the working part or verifiers after instrumental processing of the canals. If the orthogonal projection is performed correctly, provided that the visiograph program is accurately calibrated and there is no projection distortion for the incisors and premolars, some measurements can be taken from the diagnostic radiogram. For multi-rooted teeth, it is preferable to measure the length of the canals using endodontic instruments (Fig. 1), an apex locator, or a three-dimensional image.
• a control image is taken immediately after the end of endodontic treatment in order to determine how well the root canals are sealed, as well as after a certain specified time in order to make sure that there are no or identify the presence of complications (Fig. 2). When examining multi-rooted teeth and in cases where there is an additional canal, in an image taken with an orthoradial beam direction (direct projection), the root canals often overlap each other, which greatly complicates the diagnosis and can lead to an error in the treatment process. To obtain a separate image of the root canals, radiography with an oblique (eccentric) direction of the central beam is used (Fig. 1). In relation to each specific case, the mesial or distal inclination (angulation) of the tube in the horizontal plane is selected (for more details, see: Rogatskin D. V., Ginali N.V. Art of dental radiography, 2007).

Ideally, maximum information about the topography of the roots and the condition of the periodontal tissues can be obtained during polypositional radiography. In this case, three images are taken for diagnostic purposes - one in a straight line, with an orthoradial beam direction, and two in an oblique projection - with a distal-eccentric (Fig. 1) and mesial-eccentric beam direction (respectively, straight, posterior oblique and anterior oblique projections).

The most important aspects of successful intraoral radiography are the standardization and consistent correction of manipulations. Under the standardization of manipulations is meant the ability of a specialist conducting a radiological examination to choose the method that is optimal for each case and take a series of identical images, regardless of the position, condition of the patient and the time separating one examination from another. That is, if the diagnostic or measurement image is recognized as high-quality, each subsequent clarifying and control must be made with the same spatial and technical settings, and each subsequent image must be identical to the previous one (Fig. 1, 2).

Rice. Fig. 1. Diagnostic and measurement images of tooth 36, taken in direct (a) and distal-eccentric projection (b). 36 - chronic apical periodontitis (K04.5) with characteristic changes on the mesial root.

Rice. 2. Control image immediately after treatment of teeth 21, 22 (chronic periapical abscess in a state of suppuration) (a) and a delayed control image 5 months after canal filling (b), the state of repair at the stage of treatment.

Description of intraoral images

All over the world, dentists themselves are directly involved in the production and description of intraoral images of teeth, therefore, each qualified specialist must not only master the basics of positioning techniques, but also know the algorithm for describing the intraoral radiogram of a tooth (IRZ, IO dental radiograph). Unfortunately, practitioners do not always interpret the image logically and use incorrect notations. For example, such a common expression as "rarefaction of bone tissue with clear boundaries" already contains three errors.

Firstly, the term "rarefaction", or rarefaction (from rare - rare), implies a decrease in tissue density due to a decrease in the amount of a solid component (decalcification), but without destroying the basic structure of bone tissue. In the classical version, rarefaction is a sign or characteristic of osteoporosis. In the process of development, for example, of a radicular cyst, and in any other periapical processes, the bone in the periapex is not preserved, it is completely destroyed, and, thus, the term "rarefaction" absolutely incorrectly characterizes the pathological process existing in the periapex.

Secondly, to describe the shape of a two-dimensional figure in the figure, use the term "contour", not "boundary". Thirdly, a qualified reading of a snapshot consists of three stages - ascertaining, interpreting and concluding. Statement means the actual description of a two-dimensional pattern in the negative image mode obtained during the study. Interpretation is a comparison of the obtained graphical data with the clinical experience of a specialist, on the basis of which a conclusion is made, that is, a radiological diagnosis is made. Thus, the definition of “clearly demarcated bone tissue” implies a statement of the visual detection of a focus of radiolucency (radiolucency) with a clear contour, which clinically corresponds to bone tissue destruction in the presence of an apical granuloma or radicular cyst. In the same way, it is incorrect, for example, to use the term “periodontal gap” in the description, since such an anatomical formation does not exist. The correct name of the structure surrounding the root visible in the picture is the space of the periodontal ligament (periodontal ligamentum).

In addition, dentists traditionally "see" only the destruction zone and completely ignore the zone of intoxication represented by perifocal osteosclerosis. This image element, represented by a zone of bone tissue compaction along the edge of destruction, indicates the presence of chronic intoxication and outlines the true extent of the pathological focus (Fig. 3). Perifocal osteosclerosis corresponds to the state of chronic abscess formation and does not occur in the presence of sterile destructive processes (benign tumors, cysts of various origins (Fig. 4), apical granulomas outside the state of suppuration (exacerbation).

Rice. 3. Intraoral X-ray of tooth 24, chronic periapical abscess (K04.6), the area of ​​bone tissue destruction with characteristic perifocal sclerosis is visually determined.

Rice. 4. Intraoral X-ray of tooth 44, radicular cyst (K04.7), no inflammatory remodeling of the perifocal bone tissue (explanation in the text).

There are many more similar nuances, but if we summarize all of the above and take into account certain traditions of describing a tooth image, the following algorithms can be recommended as a scheme.

1. Pulpitis.

1.1. On the intraoral periapical image (as an option, IRZ, intraoral radiogram of the tooth) of tooth N, pathological changes in the bone tissue in the region of the root apex are not visually determined (option: there are no visible pathological changes).

1.2. The expansion of the space of the periodontal ligament in the periapical region is determined.

1.3. Expansion of the space of the periodontal ligament with fragmentary destruction (remodeling, deformation) of the closing plate of the alveolar wall
in the periapical region.

1.2.1. The shadow of the filling material in the canal is not traced.

2. Acute and chronic apical periodontitis (K04.4; K04.5).

2.1. On the intraoral periapical X-ray of tooth N, pathological changes in the bone tissue in the region of the root apex are not visually determined.

2.2 . The expansion of the space of the periodontal ligament in the periapical region is determined.

2.3 . Expansion of the space of the periodontal ligament throughout.

2.4 . Expansion of the space of the periodontal ligament throughout, destruction of the hard plate of the alveolus (lamina dura) in the periapical region.

2.5. In the periapical region, there is an increase in the density of the bone pattern in the form of perifocal osteosclerosis without clear contours, clinically corresponding to the state after endodontic treatment with residual intoxication.

2.6.1. In the periapical region, a shadow is visually determined, corresponding in density and configuration to the filling material.

2.6.2. The shadow of the filling material is determined in the form of several fragments (conglomerate) located in close proximity to the apex (at a distance of N mm).

2.6.3. It is defined as a continuous linear structure, corresponding in density and configuration to a fragment of a gutta-percha pin (the length is indicated).

2.7.1. The shadow of the filling material in the canal is not traced.

2.7.2. Tracked throughout.

2.7.3. It can be traced fragmentarily, radiologically the apex is obturated.

2.7.4. It can be traced fragmentarily, located near the wall, the shadow of the filling material is heterogeneous (other), the apex is not obturated.

2.7.5. Can be traced from the mouth for ½ of the length of the root, the lumen of the root canal in the apical part of the root is not visually determined (not traced).

2.7.6. The lumen of the root canal is not visible throughout the root.

2.7.7. In the region of the middle third of the root, a shadow of metallic density is visually determined, the configuration corresponding to a fragment of an endodontic instrument (canal filler? other, the length of the fragment is indicated).

3. Periapical abscess (K04.6-7), apical granuloma, radicular cyst (K04.8).

3.1. In the region of the root apex, destruction (ratiolucency, radiolucent) of the bone tissue is visually determined without clear contours, in the form of an area of ​​reduced density, with partial preservation of the characteristic bone pattern (the length is indicated).

3.2.1. The radiolucency is determined, corresponding to the destruction of bone tissue, extending (for example) from the middle third of the distal surface of the root N to the region of the interalveolar septum.

3.2.2. In the area (for example) of the middle third of the root, a linear decrease in the density of the pattern with a transverse extent is determined, clinically corresponding to a violation of the integrity of the hard tissues of the root (fracture) without displacement of the fragments.

3.3. In the region of the root apex, radiolucency is visually determined, corresponding to the destruction of bone tissue, with clear rounded contours (the length is indicated).

3.4. A focus of bone tissue destruction with clear contours of a rounded shape (the length is indicated), along the contour of the focus, an increase in the density of the bone pattern of the surrounding tissue in the form of perifocal osteosclerosis without clear contours is determined along the entire length.

3.5. In the lumen of the focus of destruction, a shadow is determined, corresponding in density and configuration to a fragment of a filling material (gutta-percha pin, a fragment of an endodontic instrument).

3.6. With clear contours of a rounded shape, with a tendency for the process to spread towards the periapical region of such and such a tooth (the adjacent tooth is indicated).

3.7. Extending to the region of the interradicular septum.

3.8. The visually determined area of ​​enlightenment (destruction) of the bone tissue is partially (in full) projected onto the area of ​​the alveolar bay of the maxillary sinus (mandibular canal, piriform opening, etc. ).

3.9. The cortical plate of the lower wall of the maxillary sinus in the area of ​​the radiolucency projection is preserved throughout (it can be traced in fragments, not traced).

3.10. The cortical plate of the lower wall of the maxillary sinus in the area of ​​the projection of destruction is preserved throughout its entire length, there is a change in its configuration and an increase in the density of the pattern of the surrounding tissues, which is defined as a rounded formation protruding into the lumen of the sinus.

About the author

Rogatskin Dmitry Vasilyevich, radiologist LLC "Ortos", Russia, Smolensk

Rogatskin D. V., radiologist, LLC Ortos, Russia, Smolensk

Annotation. Radiation diagnostics in dentistry is one of the main and most popular research methods. The article describes the popular methods of radiation diagnostics, provides a description of intraoral images, as well as algorithms for specific clinical situations.

Algorithm for intraoral radiation research and description of dental images

Annotation. Radiation diagnostics in dentistry is one of the main and most popular research methods. The article describes the popular methods of radiation diagnostics, provides a description of intraoral images as well as algorithms in specific clinical situations.

Keywords: radiology; radiovisiography; intraoral picture.

Key words: radiation diagnostics; radiovisiography; intraoral image.

Kalashnikov Club | The basis of a precise shot: rules for aiming

Georgy Gubich, a Kalashnikov specialist in the field of civilian small arms, talks about the rules for using a closed mechanical diopter sight

More than a year ago, the article “Mechanical sights. Types and features ”, where I tried to give information for reflection on what are the fundamental differences between open and closed sights, as well as describe the differences in aiming methods. It turned out that the article, in addition to not convincing everyone, in some cases raised even more questions than it answered, and sometimes even led to outbursts of rage in an attempt to deny the obvious.

I think this happened due to the fact that, in fact, some readers perceived the analytical material as the rules for aiming with a diopter sight, and even superimposing on it the established aiming technique with an open mechanical sight.

Therefore, in this article I focus on the rules for using mechanical sights - open and diopter. But first, let's turn our attention to the ability to achieve shooting targets by taking the rules for using scopes out of context.

I would like to start with quotes from a book that can rightfully be considered the quintessence of Soviet methods of sports shooting - A.A. Yuryev, "Sport Shooting", Moscow, FIS, 1962 (Second Edition):

“An indispensable condition for correct aiming should be such a mutual arrangement of sights (regardless of the types of sights) in which a “smooth front sight” is maintained.

When aiming with an open sight, a “flat front sight” will be such a visible arrangement of sighting devices in which the front sight falls in the middle of the sight slot, and the top of the front sight is flush with the upper edges of the slot.

“When aiming with a diopter sight with a “flat front sight”, the top of the rectangular front sight (or the center of the hole of the ring front sight) will be aligned with the center of the diopter hole.”

Thus, the “flat front sight” for an open sight is the top of the front sight at the same level as the top of the rear sight, the side gaps (if any) are the same size, and the “flat front sight” for a diopter sight is the top of the front sight in the center of the diopter hole.

For open sight:

1. Front sight in the middle of the slot

2. The top of the front sight is at the level of the mane of the rear sight

The figures presented in this article are schematic and not capable of conveying the full picture, but will help you visualize the main theses of the article.

For diopter sight:

1. The top of the front sight is in the center of the rear sight hole

Separately, it is worth focusing on the fact that in the case of a diopter sight, we are talking about the top of the front sight, and not its other part (middle, 2/3, etc.). Perhaps you yourself have encountered similar manifestations in your practice:

From the point of view of directly building the correct sighting line, you can aim not with the top of the front sight, but, for example, with its base or protection, and, subject to the condition of uniformity, such options will also work. But there is no need to talk about ease of use. We must not forget about the different types of flies, types of protection and the position of the flies relative to the protection (because the vertical displacement of the STP when bringing the weapon to normal combat is often carried out by screwing in or twisting the front sight), and getting used to centering relative to the diopter hole, for example, a round front sight , you can run into a problem when picking up a weapon that does not have a trigger.

Regardless of the conditions, the position of the top of the front sight in the center of the diopter is optimal.

Again we return to quotes from the book of A.A. Yuryev "Sport Shooting" (Second Edition, Moscow, FiS, 1962):

“Thus, the accuracy of aiming depends on the ability of the shooter to always keep the “smooth front sight” in the same way and combine its top with the lower edge of the “apple” of the target (with the aiming point).

At first glance, the aiming scheme outlined above seems simple and understandable. But when the shooter wants to put it into practice, he will face many difficulties during shooting.

The main practical difficulties that arise in front of the shooter during aiming are due to the peculiarities of the structure of the eye and its work as an optical apparatus in the process of aiming.

“. .. the eye cannot simultaneously clearly see objects located at different distances from it, in this case, the sight slot, the front sight and the “apple” of the target. So, if you clearly see the front sight, then the target and the slot of the sight will be perceived by the eye as blurry; if you focus your vision on the target, the front sight and the slot of the sight will be blurry. Some shooters, while aiming when firing from a rifle, “run across” their gaze from the front sight to the slot, then to the third object - the target, doing this quickly and several times until they combine all three points on one straight line. This method of aiming causes rapid fatigue of the muscular apparatus of the eye and can be used in the initial form of learning to aim, and then only at first. With this method of aiming, it is very difficult for the shooter to conduct, for example, high-speed shooting when it is limited by time. The same applies to standing shooting, when the athlete does not have the opportunity to pay much attention to aligning and refining the position of the front sight in the slot. Therefore, while aiming when shooting from a rifle, the shooter must sacrifice something and strive to clearly, sharply see only one of three objects: either the front sight, or the slot, or the target.

Based on practice, the vast majority of shooters, when shooting from a rifle, try to see the front sight sharply, being forced to somewhat neglect the sharpness of the image and the cut of the sight and the "apple" of the target. At the same time, one should not be embarrassed by the fact that the sight slot is perceived as fuzzy and, as it were, doubled ... "

At first glance, everything is quite simple, obvious and has long been known. Almost the same thing can be seen in the manual on shooting (NSD), for example:

"119. To aim, you need to close your left eye, and look with your right eye through the slot of the sight at the front sight so that the front sight falls in the middle of the slot, and its top is on a par with the upper edges of the mane of the aiming bar, i. e., take an even front sight.

© Guide to the 5.45 mm Kalashnikov assault rifle (AK74, AKS74, AK74N, AKS74N) and 5.45 mm Kalashnikov light machine gun (RPK74, RPKS74, RPK74N, RPKS74N). Moscow: Military publishing house of the Ministry of Defense of the USSR, 1976.

We level the front sight vertically and horizontally - and "there will be happiness."

It is worth noting that the NSD does not say anything about what specifically needs to be focused on, therefore, the correct formation of the skill remains on the conscience of the leader at the training place.

This is what concerns working with an open sight. Further about the diopter. And again we return to A.A. Yuryev’s “Sport Shooting” (Second Edition, Moscow, FiS, 1962):

“A diopter sight greatly facilitates and simplifies aiming, since the shooter is relieved of the need to see one of the three objects (sight slot) during shooting, which is closest to the eye, and therefore the most inconvenient for visual perception.

The role of the slot in the diopter sight is performed by a small round hole (diopter). When aiming, the shooter needs to look through it and see only two objects - the front sight and the target.

To aim with a diopter sight, the shooter, looking through the diopter hole with his right eye, brings the top of the rectangular front sight under the lower edge of the target "apple" or places the "apple" of the target in the center of the front sight ring.

During aiming, the shooter should not particularly divert his attention to searching for the center of the diopter hole and aligning the top of the front sight with it; due to the sense of symmetry of the eyes, this work is able to perform automatically and involuntarily.

If the shooter makes an inaccuracy in determining the center of the hole and the location of the top of the front sight in it, and the line of sight turns out to be somewhat shifted to the side, there will be no big mistake in aiming, because the point of the diopter hole itself is relatively small.

Thus, in order to ensure accurate and uniform aiming with a diopter sight, the shooter must basically mobilize all his attention to correctly and uniformly position the top of the front sight relative to the aiming point, while carefully maintaining the same clearance.

Likewise, there are no secrets.

If we turn to foreign sources, for example, an analogue of our NSD - Field manual, we will find that it says about the same principles of a “smooth front sight”.

Figure 4-15. Correct sight alignment

RIFLE MARKSMANSHIP M16A1, M16A2/3, M16A4, AND M4 CARBINE (Change 4). Washington: US Army, 2006.

RIFLE MARKSMANSHIP M16-/M4-SERIES WEAPONS (Change 1). Washington, DC : HEADQUARTERS DEPARTMENT OF THE ARMY, 2011.

The referenced Field Manual FM3.22-9, although without much detail, mentions that centering the front sight in the rear sight hole ring, the eye is able to perform independently.

But in reality, many have doubts, bordering on distrust, regarding the possibility of automatically centering the front sight in the diopter ring. The fact is that here we are hindered by stereotypes formed by the experience of working with "open mechanics". If you are shooting for the first time using a diopter sight, then instinctively you want to center the geometric center of the visible part of the front sight. We have already seen that this is not true, although, as discussed in the first article, a small shift will not lead to catastrophic consequences.

It must be remembered that the top of the front sight is located in the center of the rear sight hole, and not its geometric center. With the development of the skill, this error disappears rather quickly, and the eye puts the top of the front sight in the center of the rear sight ring. Let's look at this through the prism of the real conditions for the use of weapons.

If you need to make an accurate shot, for example, at a distant small target, you can always take a fraction of a second to control the position of the top of the front sight in the diopter hole, while preparing a quality preparation for an accurate shot. And if you need to make a quick shot, your focus will be on the target, which you will automatically place in the center of the diopter, and small possible deviations of the front sight (which, by the way, is more clearly visible due to the effect of increasing the depth of field) from the center of the rear sight ring will not give a significant absolute deviation of the bullet from the aiming point, tk. if you needed to make a quick shot, then most likely the target is close and large-sized.

Let me draw your attention to one more nuance from our NSD, namely, to the part where it is written “you need to close your left eye”! As is often the case in manuals, there is no description and explanation of why it is necessary to squint your eyes, since such documents are made according to the “read-do” principle and are aimed (or contribute) to simplifying the procedures for further copying to students. It can be assumed that in this way an attempt is made to increase control over the sighting image and the "smooth front sight" by cutting off half of the visual field or, which may be even more priority, an attempt to forcibly get rid of the problem of determining the "leading" eye.

And again we return to quotes from A.A. Yuryev’s “Sport Shooting” (Second Edition, Moscow, FIS, 1962):

“... the tension associated with closing the left eye, painful for many, especially for beginners shooters. Another disadvantage is that closing one eye is almost always accompanied by more or less tension in the muscles of the eyelids and pressure of the eyelid of the aiming eye on the eyeball; the latter affects the light-refracting apparatus and thereby negatively affects visual acuity. The third point that adversely affects the accuracy of shooting is the involuntary expansion of the pupil of the open eye in response to covering or closing the other. Based on this, it is best to turn off the second eye from the work not by physical means - by closing, but by psychological suppression of the visual impressions of the open, not aiming, left eye.

It follows from the text that closing one's eyes has many negative aspects.

To consciously suppress the perception of the picture by the “guided” eye, the following training method can be used: at the initial stage of mastering the aiming technique, the shooter closes his left eye, then learns to aim with both eyes, first slightly squinting his left eye to produce an accurate shot, then gradually opening his eye more and more , proceeds to shoot with both eyes open. In case of lack of time for full-fledged training, it is possible to use a simple algorithm in training the shooter: close your eye - level the front sight.

The described training methodology allows achieving a high quality of aiming in classical bullet shooting and, for example, in applied military exercises AK-3 and AK-4, and if other skills necessary for firing a shot are available at a high level, a high level of shooting accuracy.

And now let's move away from the mentioned conditions a little, when:

1. the target is static;
2. target contrast;
3. the target is well lit.

And consider, for example, the conditions for performing exercises according to the rules of the international confederation of practical shooting from a carbine in the open air.

A beige cardboard target against a sand bank or a white target against a snowy shooting range will have low contrast and may be poorly lit, such as side or contrast light. Under such conditions, keeping a "smooth front sight" and combining its top with a faintly distinguishable target will become a non-trivial task. And in the case of using “focus on the front sight”, it will lead to the need for constant refocusing of the eye (accommodation) from the front sight to the target and back to clarify the correct aiming.

Or another situation: the bullet shooter knows for sure that it makes no sense to look at the target after the shot - black holes in the black "apple" of the target at 50/100/300 meters still cannot be seen. The practical shooter also knows not to look at cardboard targets. But, after shooting at a metal falling target - “popper”, even if the shooter is mentally able to make a good “mark” of the shot and the sound of a bullet hitting was heard, it is necessary to look at the target and make sure that the target has fallen. Otherwise, it will be considered unaffected. And here a diopter sight is more convenient than an open one - refocusing, if it is needed at all, is much easier and faster.

In these cases, the use of diopter sights makes it possible to significantly simplify these tasks: there is no need to level the front sight in the rear sight, as already mentioned in the quote from Sports Shooting - the eye performs this function involuntarily; increasing the depth of field makes aiming easier, there is no need for additional accommodation of the eye. In a diopter sight, when focusing on the front sight, the “blurring” of the target is much less than when looking through an open sight.

If we are guided by the contents of the manuals on shooting (NSD), then for the successful completion of tasks in combat, at a minimum, it is necessary:

If you close one eye while shooting, at least 30% of the field of view is cut off. Is it right to close your eyes in this case? The question is rhetorical.

"Skillfully shoot at all kinds of targets"

A properly trained shooter should be able to do this regardless of the type of sight on his weapon. Do not forget also about the ability to determine the distance to the target, as well as the removal of the aiming point in accordance with the excess of the trajectory, if necessary.

“Observe the results of the fire and skillfully correct it”

It is worth noting here that the manuals list specific methods of observation and evaluation: bursts of hits, bullet tracks and changes in the behavior of the enemy. front sight, the top of a clearly visible front sight on the target blur. If the paths of tracer bullets are more or less visible at the same time, then observing the bursts will require a shift in the gaze to the target and the space surrounding it. And how long will it take to transfer focus from the front sight to the target, for example, at 200 meters, and back? A second and a half? Plus or minus.

So it turns out - either the correct aiming picture, or a timely and, with a greater degree of probability, an effective shot.

Let's imagine a more realistic situation. The enemy in camouflage disguises himself in thickets and moves at the same time. How can you generally fire at such a target, focusing on the front sight, while observing the results of the shooting and adjusting it if necessary, if the target is already barely distinguishable and changes its position?

The answer is simple - when using an open sight, aiming in accordance with the canonical rules from the textbook is often impossible. They shoot, sacrificing accuracy - focusing on the target with blurry front and rear sights. And with the advantages of a diopter sight, expressed in an increase in the depth of field and the absence of the need for perfect focusing on the front sight, aimed fire at a complex target merging with the background is real: tracks are visible (when using tracer bullets), bursts of hits are visible and enemy behavior is visible - remains on place, took cover or fell stricken.

Do not forget also that when looking through an open sight, the shooter, maintaining a "smooth front sight", does not see the space below the level of its top. When looking through the rear sight, there is an observable field below the top of the front sight.

Why do dissatisfaction and denial arise among those who, having extensive experience in shooting with an open mechanical sight, tried to shoot with a diopter sight?

As a rule, everything lies in the wrong use. Shooters complain about the narrow field of view in the sight, about the rear sight itself, which blocks part of the view, that the front sight is “impossible” to center in the diopter ring.

But, if you follow simple rules, which, unfortunately, are little known, then everything becomes much simpler and clearer.

First, position the eye at a distance of 4-8 cm. At this distance from the eye to the diopter hole, a balance is maintained between the angle of the field of view through the diopter hole and the ease of intuitively positioning the top of the front sight in the center of the hole. In this case, the rear sight ring blurs into a ghostly shadow and becomes almost invisible. A shooter who does not close his eyes when shooting cannot lose part of his field of vision at all, because the brain will supplement the entire missing picture from the right pupil with information from the left. The required distance from the diopter to the eye can be maintained either by correcting the manufacture, or by changing the length of the adjustable stock. By the way, it is not possible to install a diopter sight on any type of small arms, precisely because of the requirements for the distance to the eye.

Secondly, If you have just started to master shooting using a diopter aiming device, you need to focus on the location of the upper cut of the front sight in the center of the diopter. In the future, to make any significant effort to center the top of the front sight in the rear sight ring, as already mentioned not only by me, but also quoted from, I’m not afraid of this word, the greatest work on teaching the technique of producing a well-aimed shot, there is practically no need - eye will do so involuntarily. The same thing was mentioned in the first article, when the ability of a diopter sight to reduce parallax was briefly described. You can read more about this effect in a recently published translation of a practical study on this topic.

Thirdly, the canonical rule "focus on the front sight." But, depending on the conditions, due to the increase in the depth of field of the depicted space, in order to achieve the goals of making a shot, it is possible to shift the focus of vision to the target without losing the quality of aiming.

And again, briefly about the rules of shooting using a diopter sight (after determining the range to the target, setting the sight and / or taking out the aiming point and forming the correct position, which will ensure the necessary removal of the eye from the sight):

• front sight focus;
• top of the front sight in the center of the diopter;
• the top of the front sight on the aiming point.

SUMMARY

ANY mechanical sighting device allows you to make an accurate shot, provided that the shooter is able to distinguish the target, it's just a matter of skill.

Learn more

• 
  Song about pink color
• 
  List of verbs for 3rd graders
• 
  Snow day stories
• 
  Teach reading skills
• 
  Song about colors for preschoolers
• 
  Things to do with four year olds
• 
  Action verb list for students
• 
  5 year old vocabulary
• 
  Southwestern advantage login
• 
  Social skill lesson
• 
  Things to do when your bored in winter